Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. Thanks Yonatan Drori (Tenzai) for reporting.
Update concrete5/concrete5 to 9.5.1 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanConcrete CMS is vulnerable to Stored XSS via page name in the Atomik theme affects concrete5/concrete5 (composer). Severity is low. Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. Thanks Yonatan Drori (Tenzai) for reporting.
AI coding agents often install or upgrade packages automatically in composer. A low vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| concrete5/concrete5composer | >=9.0.0RC.1,<9.5.1 | 9.5.1 |
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. Thanks Yonatan Drori (Tenzai) for reporting.
Update concrete5/concrete5 to 9.5.1 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanConcrete CMS is vulnerable to Stored XSS via page name in the Atomik theme affects concrete5/concrete5 (composer). Severity is low. Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. Thanks Yonatan Drori (Tenzai) for reporting.
AI coding agents often install or upgrade packages automatically in composer. A low vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| concrete5/concrete5composer | >=9.0.0RC.1,<9.5.1 | 9.5.1 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL GuardFixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard